1. Field of the Invention
This invention relates to an automatic welding apparatus for use with a workpiece comprising plural divided parts, and which is so operated that the parts are first fixed with a temporary weld to form an integral unit, and the integral unit is then additionally welded to form a workpiece product.
2. Description of the Prior Art
In welding apparatus, as disclosed in Japanese Patent Publication No. Sho 56-7473, for instance, a jig table for workpiece setting is reciprocated, by means of a conveying means which extends in the front to rear direction, between a welding station in the front and a setting station in the rear. A first welding means for temporary welding and a second welding means for additional welding are provided at the welding station and operate alternatively. Thus, after a workpiece set on the jig table is temporarily welded by the first welding means, the jig table is moved upwards so that the workpiece may be transferred to a workpiece holding means provided at an upper portion of the welding station. After the transfer of the workpiece, the jig table is moved back to the setting station, and during this time, the workpiece, held by the holding means, is additionally welded by the second welding means, and during the additional welding operation, a setting operation of the next workpiece on the jig table may be carried out at the setting station.
This type of welding apparatus, however, is inconvenient in that the next additional weld on the next workpiece cannot be carried out unless procedural steps are completed, after the completion of the additional welding. Specifically, the jig table is moved to be introduced into the welding station, and thereafter, the temporary weld is made on the earlier workpiece and the transfer thereof to the holding means by elevating of the jig table is carried out.